Numerical thermal performance study in a heat exchanger tube with discrete V-ribs

Main Article Content

N. Koolnapadol
S. Skullong
T. Sutthanonkul
P. Loraphong
T. Sooksin

Abstract

The paper presents a numerical investigation on heat transfer enhancement in a heat exchanger tube fitted with discrete V-ribs by calculating a three dimensional, steady turbulent tube flow model. The six pairs of discrete Vshaped ribs mounted around the tube circumference are used to produce counter-rotating vortices inside the tube that can convey the colder fluid in the core flow to the heated-wall region. The test fluid is water having the flow rate in terms of Reynolds number from 3000 to 25,000. The rib parameters are the attack angle of 45º, two relative rib lengths (L/D=0.2 and 0.3), four pitch ratios (PR=P/D= 0.24, 0.32, 0.48 and 0.64) and a single relative V-rib height (BR=e/D= 0.02). The computation reveals that the tube with circumferential discrete V-ribs provides considerably higher thermal performance than the smooth tube in the range of 1.26 - 2.14. The maximum thermal performance of 2.14 is found for using PR=0.24, L/D=0.3 at Re=3000.

Article Details

How to Cite
Koolnapadol, N., Skullong, S., Sutthanonkul, T., Loraphong, P., & Sooksin, T. (2018). Numerical thermal performance study in a heat exchanger tube with discrete V-ribs. Journal of Research and Applications in Mechanical Engineering, 4(2), 192–201. Retrieved from https://ph01.tci-thaijo.org/index.php/jrame/article/view/138673
Section
RESEARCH ARTICLES

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